squirt bottle from walmart: 1 dollar
the acid may eat the metal parts inside of it, that happened to mine but it still worked for half a year, just spray it a few times to get the rust out if that happens
just cut a hole and then seal it off with some rubber sealant from walmart
you should also probably get a vent that way you can shut it off if it's taking too much away from your house
you can get infra red webcams for 5 dollars each in bulk then purchase lots of usb cable and usb hubs and some software that can access all the streams to record and a high speed large hard drive in the machine recording all of the video feed